696 Proceedings of the Royal IrisJi Academy. 



mountains are almost continuous. The real difference lies north and 

 south of Clew Bay. South of this bay, which is continuous with low 

 levels inland, alpine species are more numerous and descend lower, 

 and this is still further the case south of the Killary in the Connemara 

 district. In one sense this is more an apparent than a real difierence, 

 since the most universal species, Salix herhacea and Carex rigida, are 

 scarcer in quantity southwards : the variety of kinds is, hovrex er, 

 greater and wider-spread. Cwrex rigida descends to an unusually low 

 level at Nephin Beg — the lowest, I think, recorded. Aira ccespitosa, 

 var. alpina, was only met with on the Mayo mountains, or on the 

 bordering chain. 



Of those more thoroughly alpine plants which never descend to 

 sea level in these mountains (or elsewhere in Ireland), only three are 

 ever met with on the exposed summits or outer ridges ; these are : 

 Salix herhacea, Carex rigida, and Lycopodium alpinum. As soon, how- 

 ever, as the ground contours downwards towards any part of the 

 horizon, except north or north-east, these disappear. On the northern 

 faces of cKffs these are, as a rule, confined to a higher zone than the other 

 alpine plants, especially Lycopodium alpinum, which rarely leaves the 

 flatter summits and shoulders. Of those which do not descend to, or 

 nearly to, sea level, Saxifraga oppositifolia has the lowest range. Croagh- 

 patrick, Maumeen, Ben Lettery, and Muckanaght, best illustrate the 

 alpine flora of the Mayo and Galway mountains. 



On Muckanaght, in The Twelve Bens, I found a Saxifi'age which 

 is, as far as I can make out, indistinguishable from S. c<Bspiiosa (Linn.) 

 Mr. Baker, who has kindly examined it, has, I am happy to say, con- 

 firmed my opinion. I have compared specimens with some brought 

 home from Greenland in 1876, and except for a more stunted habit in 

 the northern plants, there appeared no difference. 



S. ccespitosa (Linn.) has rested hitherto as an Irish plant upon 

 the evidence of an imperfect specimen fi'om Brandon, gathered in 

 1829.^ No fonn of 8. hypnoides has been previously discovered in 

 the Mayo or Galway mountains. Some plants at the lower part 

 of its range on Muckanaght approach so closely to S. platypetala, 

 especially to the form on the Galtee mountains, that my belief 

 was confirmed that these forms are inseparable to a degree worthy 

 of specific rank. Higher up on the cliffs the Muckanaght Saxi- 

 frage is fairly typical S. ccespitosa. Any stunted flowering stems 

 of S. affinis or S. hirta which I have met with elsewhere in Ireland 

 have several leaves on the stem. The Connemara plant has only 

 one, or in rare instances, two. This is an important character, and 

 also separates and is distinctive of the larger and somewhat strag- 

 gling plant at the base of the mountain fi'om ;S'. platypetala. The 

 flowers in the Connemara plant are fewer, usually one to three, and 

 even in the larger forms nearly sessile; in S. platypetala they are 



1 A. G. Mere — '• Eeeent Additions to the Flora of Ireland." 



